A night out for Bertha

A section of the SR 99 tunneling machine’s trailing gear is lowered into the pit where tunneling will start this summer. Weighing more than 400 tons, this piece of the machine will house equipment to support tunneling as the machine makes its way under downtown Seattle. It was lowered at night because daytime crews are working to complete the pit. Learn more about Bertha, the SR 99 tunneling machine, at her webpage or follow her on Twitter @BerthaDigsSR99.